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991.
992.
BACKGROUND & AIMS: Hyperhomocysteinemia, a risk factor for thrombosis, recurrent miscarriages, and osteoporosis, might derive from acquired folate and vitamin B 12 deficiencies and from a C677T mutation in methylene-tetrahydrofolate reductase (MTHFR) gene. Undiagnosed gluten-sensitive enteropathy (GSE) is associated with vitamin deficiencies, osteoporosis, and recurrent miscarriages. We evaluated the prevalence and the risk factors for hyperhomocysteinemia in patients with newly diagnosed GSE. METHODS: In this prospective study performed in a tertiary care setting, 40 consecutive subjects with newly diagnosed GSE were evaluated for homocysteine, folate, and vitamin B 12 levels and for C677T polymorphism. One hundred twenty sex- and age-matched healthy control subjects were studied. Nonparametric tests and multiple regression analysis were used to evaluate the risk factors in inducing hyperhomocysteinemia in the GSE population. RESULTS: Hyperhomocysteinemia was more frequent in GSE patients than in control subjects (8/40, 20.0% vs 7/120, 5.8%) (relative risk, 3.4; 95% confidence interval, 1.3-8.9), as well as folate deficiency (17/40, 42.5% vs 10/120, 8.3%) (relative risk, 5.1; 95% confidence interval, 2.5-10.2). Multiple regression analysis showed that folate and B 12 levels were independently and inversely associated with homocysteine levels, whereas homozygosity for the MTHFR thermolabile variant was not. The prevalence of MTHFR variant in GSE population was not different from that reported in racially comparable control groups. Gluten-free diet was able to normalize folate, vitamin B 12 , and homocysteine levels. CONCLUSIONS: Hyperhomocysteinemia is frequent in newly diagnosed GSE. Vitamin deficiencies caused by malabsorption are the most important determinants of this condition. Hyperhomocysteinemia might contribute to the occurrence of common complications of undiagnosed GSE.  相似文献   
993.

Purpose

Late cure after a previously failed ablation of ventricular arrhythmias (VAs) is a relatively common phenomenon. The present study sought to delineate the incidence and electrophysiological characteristics of late cure in idiopathic VA patients.

Methods

Totally, 45 idiopathic VA cases (mean age 44?±?18 years, 27 males) either failed acutely or recurred within 12 h were enrolled in this study. Based on intensive clinical observations in the acute period, 19 (42%) patients demonstrated late cure in the first week after the procedure.

Results

The late cure patients had significantly better acute and cumulative ablation effects during the procedure than did those without a late cure. Additionally, they had a prediction that originated from the right ventricular outflow tract, aortic-mitral continuum, and left summit area relative to other sites (13/18 vs 6/27, p?<?0.01). In a median follow-up of 24 [14, 46] months, 7/19 (37%) patients had their VAs recurred. The late cure group had significantly more patients cured at long-term follow-up than those without (12/19 vs 0/26, p?<?0.01). A cutoff value of the “time to eliminate VAs” >?7.0 s was able to predict a long-term recurrence of the VAs with 62.5% sensitivity and 85.7% specificity.

Conclusions

The late cure of VAs occurs in more than one third of patients who have a seemingly unsuccessful ablation session, which is clustered in the first week after the procedure. However, long-term recurrence of VAs occurred in 37% of the late cure patients, emphasizing the importance of long-term follow-up.
  相似文献   
994.
Sara Markowitz 《Health economics》2014,23(11):1353-1373
Fires and burns are among the leading causes of unintentional death in the USA. Most of these deaths occur in residences, and cigarettes are a primary cause. In this paper, I explore the relationship between smoking, cigarette policies, and fires. As smoking rates decline, there are fewer opportunities for fires; however, the magnitude of any reduction is in question. Using a state‐level panel, I find that increases in cigarette prices are associated with fewer residential fires and deaths. However, laws regulating indoor smoking are associated with more fires; in particular, restaurant and bar smoking bans are associated with an increase in fires at eating and drinking establishments. This increase is important given the growing popularity of smoking bans in the USA and around the world. As workplaces, schools, and businesses ban smoking and remove ashtrays, smokers who continue to smoke are left without safe options for disposal of cigarettes, leading to more opportunities for fires to start. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
995.
Although poor sleep quality and associated sleep disorders are associated with increased risk of job injury and multiple mental and physical health problems, scant research has examined sleep quality among Latino farmworkers. Interviews were conducted with 371 male Latino farmworkers working in North Carolina during the 2010 agricultural season. Data on housing quality and sleep quality were collected. Access to air conditioning was significantly and positively associated with good sleep quality. This association remained when other housing characteristics and individual health indicators were controlled. Good sleep quality was associated with low levels of pain, depression, and anxiety. Poor sleep quality among Latino farmworkers was associated with poorer indicators of health. One important indicator of housing quality, air conditioning, was associated with better sleep quality. Further research is required to delineate how to improve the adequacy of farmworker housing to improve sleep quality and other health indicators.  相似文献   
996.
997.
Women with polycystic ovary syndrome (PCOS) exhibit elevated androgen levels, oligoanovulation, infertility, and insulin resistance in metabolic tissues. The aims of these studies were to determine the role of insulin signaling in the development and function of ovarian theca cells and the pathophysiologic effects of hyperinsulinism on ovarian function in obesity. We disrupted the insulin receptor (IR) gene specifically in the theca-interstitial (TI) cells of the ovaries (Cyp17IRKO). No changes in reproductive development or function were observed in lean Cyp17IRKO female mice, suggesting that insulin signaling in TI cell is not essential for reproduction. However, when females were fed a high-fat diet, diet-induced obesity (DIO) wild-type (DIO-WT) mice were infertile and experienced increased circulating testosterone levels, whereas DIO-Cyp17IRKO mice exhibited improved fertility and testosterone levels comparable to those found in lean mice. The levels of phosphorylated IRS1 and CYP17 protein were higher in the ovary of DIO-WT compared with DIO-Cyp17IRKO or lean mice. Ex vivo studies using a whole ovary culture model demonstrated that insulin acts independently or additively with human chorionic gonadotropin to enhance androstenedione secretion. These studies reveal the causal pathway linking hyperinsulinism with ovarian hyperandrogenism and the infertility of obesity.  相似文献   
998.
Prostate cancer (PCa) remains a principal cause ofmortalityin developed countries.Because no clinical interventions overcome resistance to androgen ablation therapy, management of castration resistance and metastatic disease remains largely untreatable. Metastasis is a multistep process in which tumor cells lose cell-cell contacts, egress from the primary tumor, intravasate, survive shear stress within the vasculature and extravasate into tissues to colonize ectopic sites. Tumor ceils reestablish migratory behaviors employed during nonneoplastic processes such as embryonic development, leukocyte trafficking and wound healing. While mesenchymal motility is an established paradigm of dissemination, an alternate, 'amoeboid' phenotype is increasingly appreciated as relevant to human cancer.  相似文献   
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